On the phase behavior of hard aspherical particles

TL;DR

This study investigates how deviations from spherical shape in hard particles influence their ability to form face-centered cubic structures, providing predictive relations for coexistence pressures based on particle shape.

Contribution

The paper introduces a linear relation to predict coexistence pressures of aspherical hard particles based on geometric parameters, advancing understanding of crystallizability limits.

Findings

Coexistence pressure correlates linearly with shape parameters.

Isotropic particles have predictable crystallization behavior.

Results explain empirical data on crystallizability limits.

Abstract

We use numerical simulations to understand how random deviations from the ideal spherical shape affect the ability of hard particles to form fcc crystalline structures. Using a system of hard spheres as a reference, we determine the fluid-solid coexistence pressures of both shape-polydisperse and monodisperse systems of aspherical hard particles. We find that when particles are sufficiently isotropic, the coexistence pressure can be predicted from a linear relation involving the product of two simple geometric parameters characterizing the asphericity of the particles. Finally, our results allow us to gain direct insight into the crystallizability limits of these systems by rationalizing empirical data obtained for analogous monodisperse systems.